EP0216096A2 - Dispositif pour la coupure par le central d'un poste branché involontairement sur la ligne dans une connexion à deux postes pouvant être branchés alternativement sur la ligne de façon automatique - Google Patents

Dispositif pour la coupure par le central d'un poste branché involontairement sur la ligne dans une connexion à deux postes pouvant être branchés alternativement sur la ligne de façon automatique Download PDF

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Publication number
EP0216096A2
EP0216096A2 EP86110895A EP86110895A EP0216096A2 EP 0216096 A2 EP0216096 A2 EP 0216096A2 EP 86110895 A EP86110895 A EP 86110895A EP 86110895 A EP86110895 A EP 86110895A EP 0216096 A2 EP0216096 A2 EP 0216096A2
Authority
EP
European Patent Office
Prior art keywords
telephone line
switching
line
switching device
station
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP86110895A
Other languages
German (de)
English (en)
Other versions
EP0216096A3 (en
EP0216096B1 (fr
Inventor
Dirk Dipl.-Ing. Neumann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Neumann Elektronik GmbH
Original Assignee
Neumann Elektronik GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Neumann Elektronik GmbH filed Critical Neumann Elektronik GmbH
Priority to AT86110895T priority Critical patent/ATE73283T1/de
Publication of EP0216096A2 publication Critical patent/EP0216096A2/fr
Publication of EP0216096A3 publication Critical patent/EP0216096A3/de
Application granted granted Critical
Publication of EP0216096B1 publication Critical patent/EP0216096B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M1/00Substation equipment, e.g. for use by subscribers
    • H04M1/71Substation extension arrangements
    • H04M1/715Substation extension arrangements using two or more extensions per line

Definitions

  • the invention relates to a device on a telephone subscriber line with two alternately automatically connectable speech units for switching off a speech station having an unwanted loop closure from the switching center, with the features from the preamble of patent claim 1.
  • control signals emitted by the switching center to trigger the test can be DC voltage signals on the one hand and AC voltage signals of specified voltage and frequency on the other hand.
  • the test can also be triggered if there is a short-circuit closing the loop in the telephone set of the subscriber line.
  • the AC voltage signals are picked up by means of a transformer connected in series in a telephone wire.
  • the object underlying the invention was to modify the older device cited at the outset in such a way that when a short circuit occurs in one of the two microphone units, this microphone unit is automatically switched off without intervention from the switching center, whereas if there is an unwanted loop closure, for example if one forgot to put the receiver on the fork, the microphone unit can be switched off from the switching center as part of a test cycle.
  • the call station should be automatically reset to the state without access from the control center, in which it can be connected to the telephone line via the changeover switching device.
  • the acceptance of the AC voltage signals to trigger the test cycle should be possible in such a way that no transformers or other inductive components have to be switched into the line.
  • the DC voltage prevailing on the telephone line is monitored by the device according to the invention, it being possible to distinguish whether there is a short circuit or only an unwanted loop closure due to the receiver not being hung up in one of the two microphone units when the voltage drops got to.
  • the defective intercom station is immediately automatically disconnected from the two-way switch, in such a way that the two shutdown devices between the two-way switch device and the call stations each a set signal is supplied so that first both call stations are disconnected and it is determined by the effectiveness of the monitoring device at both call stations, in which of the two call stations there is no short circuit and this call station is immediately automatically reconnected to the two-way switching device. Calls can then be made from this call station immediately, while the defective call station remains switched off until the short circuit is eliminated.
  • this loop closure is ascertained when the telephone line is checked by the switching center. In this case, too, a set signal is fed to both shutdown devices, so that both microphone units are disconnected from the two-way switching device. In this case, the monitoring device determines after the end of the test cycle in which of the two call stations the loop is interrupted and switches this call station back to the change-over switching device, while the other call station remains disconnected until the unwanted loop closure is eliminated.
  • a telephone line a0, b0 coming from a switching center, not shown, is connected via switching contacts s to a further section of the telephone line a1, b1, which leads to a changeover switching device W, to the two microphone units Sp1 and Sp2 of the subscriber line are connected, which can be alternately connected to the telephone line a1, b1 via the changeover switching device W.
  • circuit parts arranged in the known changeover switching device which essentially consist of bistable relay circuits and loop current detection circuits, are not shown and are not described in more detail below.
  • the output a11 is connected to the wire a1 and the output B1 is connected to the wire b1 of the telephone line, and the output b21 is separated from the wire b1.
  • the output a21 is connected to the wire a1 and the output B2 is connected to the wire b1 of the telephone line and the output b11 is separated from the wire b1.
  • a device for testing the telephone line from the switching center which has a switchover device U and a test device P, is arranged in front of the changeover switching device W, as shown in FIG. 1.
  • the switchover device U can be controlled on the one hand by a DC voltage control signal, for example an increase in the line voltage to 100 V, and on the other hand by an AC voltage signal.
  • the switching device U contains a DC voltage control switch 2 which is connected to the two branches a1, b1 of the telephone line and which responds to an increase in the line voltage.
  • This same Voltage control switch 2 can also be constructed in a manner known per se so that it responds to a brief reversal of the polarity of the DC line voltage.
  • the control input of a control switch 9 is connected to the branch a0, b0 of the telephone line coming from the exchange in parallel connection via an active filter 3 and a switching amplifier 5.
  • the output of the control switch 9 is connected to a first winding S1 of a bistable relay, the switch contacts s of which are arranged in the telephone line a0, b0, viewed from the switching center, in front of the connection point of the DC voltage control switch.
  • the input of the control switch 9 and the feed inputs of the switching amplifier 5 and the active filter 3 can be connected to the telephone line a0, b0 via a controllable switching device 18.
  • the DC voltage control switch 2 is also connected to the first winding S1 via the control switch 9.
  • the subscriber connection can be connected again to the telephone line a0, b0 via the contacts s.
  • the test device P contains a device 7 connected via a rectifier bridge 6 arranged for protection against line reversals and a current stabilizer 1 for generating the supply voltages necessary for the test device. It also contains a low-frequency generator 8, the output of which signals can be fed via a capacitor C1 to the telephone line a0, b0. In a manner not shown, the low-frequency generator can emit signals with fixed, predetermined frequencies or be swept over a certain frequency range.
  • the test device P shown in Fig. 1 further comprises a first monitoring device P1, which continuously determines whether the DC voltage prevailing on the telephone line when the subscriber line is connected is, for example as a result of an unwanted loop closure, below a predetermined maximum value, but still above the minimum value signaling a short circuit.
  • a first voltage sensor 17 is connected via a rectifier bridge 10 to the telephone line a0, b0 in front of the switch contacts s.
  • the output of the first voltage sensor 17 is connected to the control input of the controllable switching device 18, by means of which the input of the control switch 9 can be connected to the telephone line in terms of direct voltage.
  • Another controllable switching device 19 connects the device 7 for generating the supply voltages to a line e1, which leads to the shutdown devices K11 and K21 described below.
  • a capacitor C20 ensures that the switching device 19 switches itself on with a delay when a voltage signal is present.
  • the test device P further comprises a second monitoring device P2 which continuously determines whether the DC voltage on the telephone line a0, b0 drops to a value below a predetermined minimum value as a result of a short circuit in the subscriber station.
  • a second voltage sensor 11 is connected to the telephone line a0, b0 before the switching contacts s, the output of which is connected to the control input of a controllable switching device 12, the input of which is connected to a storage capacitor C13, which is also constantly connected to the telephone line a0 via a diode D14 , b0 is connected.
  • the output of the controllable switching device 12 is in turn connected to the line e1 leading to the switch-off device K11, K21.
  • switch-off devices K11 and K21 are arranged between the two-way switching device W and the two intercom stations Sp1 and Sp2, by means of which a resettable disconnection of the intercom stations Sp1 and Sp2 from the two-way switching device W is possible.
  • the shutdown device assigned to the intercom Sp1 is a bistable relay with a set winding K11 and a reset winding K12.
  • the switch contacts k1 of this relay are arranged so that they connect the output b11 of the changeover switching device W to the intercom Sp1 in the non-set state.
  • the set winding K11 is connected to the line e1 via a set input e11.
  • a monitoring circuit 16 which is explained in more detail below and which contains the reset winding K12, is on the one hand permanently connected to the intercom station Sp1 via a reset input RS1 and a line b10 and can be connected to the outputs a11, b11 of the changeover switching device W via the switch contacts k1.
  • the switch-off device assigned to the conference unit Sp2 is a bistable relay with a set winding K21 and a reset winding K22 and switch contacts k2, via which the output b21 is connected to the conference unit Sp2 in the non-set state.
  • the monitoring device 26 has the reset winding K22 and is connected to the call station Sp2 via the reset input RS2 and can be connected to the outputs a21 and b21 of the changeover switching device W via the switch contacts k2.
  • the set winding K21 is connected to the line e1 via the set input e21.
  • the output B1 of the changeover switching device W is connected to the test device P via a line d1 in the manner shown in FIG. 1, while in an analogous manner the output B2 is also connected to the test device P via the line c1.
  • FIG. 3 serves to explain the structure of the monitoring device 26 in more detail.
  • the monitoring device 16 is constructed analogously.
  • the reset winding K22 of the bistable relay is located in the monitoring device 26 in a circuit which is connected from a rectifier bridge 24 connected via the switching contacts k2 to the outputs a21 and b21 of the changeover switching device W via a transistor Tr23, the relay winding K22 and a thyristor Th2 runs back to the rectifier bridge 24.
  • this circuit runs a control circuit which is connected from the reset input RS2 to the base of the transistor Tr23.
  • this microphone unit Sp2 is constantly connected to the telephone line a1, b1 via the switching contacts k2 and the outputs a21, b21 due to the mode of operation of the changeover switching device W. This means that the station Sp1 is disconnected and no calls can be made from it.
  • the second voltage sensor 11 detects that the voltage on the telephone line a0, b0 has dropped to a value below a predetermined minimum value, for example to a value below 2V. It emits a control signal by means of which the switching device 12 is switched through and the line e1 is connected to the storage capacitor C13 which still has a stored voltage value. The result of this is that a setting signal is supplied to the setting inputs e11 and e21 via the line e1 and the setting windings K11 and K21 are thus activated, as a result of which the contacts k1 and k2 are flipped over and thus both microphone units Sp1 and Sp2 are separated from the changeover switching device W.
  • the transistor Tr23 remains blocked because, as a result of the short circuit in the call station Sp2, the base of the transistor Tr23 is connected via this short circuit to the output a21 of the changeover switching device W, which carries negative voltage. No current flows through the reset winding K22.
  • the transistor Tr23 switches through, the reset winding K22 is activated and the intercom station Sp2 is again connected to the changeover switching device W.
  • this microphone unit Sp2 is constantly connected to the telephone line a1, b1 due to the mode of operation of the changeover switching device W, while the microphone unit Sp1 is disconnected and no calls can be made from it.
  • the facility for checking the telephone line must be activated. This usually happens - that is, if there is no loop closure in the subscriber station - by one from the exchange Voltage increase on the telephone line, for example from 60 V to 100 V.
  • This DC voltage control signal activates the DC voltage control switch 2 in the switching device U and thus excites the relay winding S1 via the control switch 9 and switches the relay contacts s.
  • the first voltage sensor 17 detects that the voltage on the telephone line a0, b0 is reduced and is, for example, in a range between 13V and 6V. In this case, the voltage sensor 17 emits a control signal by means of which the controllable switching device 18 is switched through.
  • an AC voltage control signal is emitted at a frequency of, for example, 800 Hz.
  • This AC voltage signal runs through the active filter 3 to the switching amplifier 5, the switching pulse of which is fed to the control input of the control switch 9, as a result of which it is switched through and the relay winding S1 is activated.
  • the test device P When the relay contacts s are switched over, the test device P is connected to the telephone line a0, b0, so that the loop is no longer effective and the full DC voltage is again present on the telephone line.
  • the device 7 for generating the supply voltages which receives its supply voltage from the telephone line, is switched on. When the device 7 is activated, all the individual devices of the test device P are switched on. In particular, a DC voltage control signal is given via line e2 to wire b1 to changeover switching device W.
  • the output B2 is connected to the wire b1, so that the same Voltage control signal runs via line c1 back to the test device P and there drives the low-frequency generator 8 so that a signal of a certain frequency is generated and given into the telephone line a0, b0, so that it can be recognized in the exchange that the disturbance is to be searched in the call station Sp2.
  • a DC voltage signal is simultaneously sent to the controllable switching device 19, which switches through and thus gives a set signal via the line e1 to both shutdown devices K11 and K21. Both switching stations are separated from the changeover switching device W via the switch contacts k1 and k2.
  • test device P After the defective call station has been disconnected, further test cycles can be carried out using the test device P.
  • the low-frequency generator 8 is swept over a frequency range of 300 to 3400 Hz, for example, in order to check the frequency response of the telephone line.
  • the relay winding S2 is activated from the time switch 4 and the changeover switching device W is reconnected to the telephone line a0, b0 via the contacts s.
  • the monitoring device 16 determines that there is no loop closure in the station Sp1 and activates the reset winding K12. In this way the microphone unit Sp1 is reconnected.
  • the monitoring device 26 determines that there is a loop closure and the intercom Sp2 remains disconnected until the loop closure is resolved.
  • a normal call can then be made again from the intact call station, while the call station at which the receiver was not on-hook remains disconnected until the receiver is replaced, which is recognized by the corresponding monitoring device 26 or 16 and for switching on again leads this station to the changeover switching device W.

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Interconnected Communication Systems, Intercoms, And Interphones (AREA)
  • Sub-Exchange Stations And Push- Button Telephones (AREA)
  • Monitoring And Testing Of Exchanges (AREA)
EP86110895A 1985-09-16 1986-08-06 Dispositif pour la coupure par le central d'un poste branché involontairement sur la ligne dans une connexion à deux postes pouvant être branchés alternativement sur la ligne de façon automatique Expired - Lifetime EP0216096B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT86110895T ATE73283T1 (de) 1985-09-16 1986-08-06 Einrichtung an einem fernsprechteilnehmeranschluss mit zwei wechselweise automatisch anschaltbaren sprechstellen zur abschaltung einer, einen ungewollten schleifenschluss aufweisenden sprechstelle von der vermittlungsstelle aus.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3532960 1985-09-16
DE3532960A DE3532960C1 (de) 1985-09-16 1985-09-16 Einrichtung an einem Fernsprech-Teilnehmeranschluss mit zwei wechselweise automatisch anschaltbaren Sprechstellen zur Abschaltung einer,einen ungewollten Schleifenschluss aufweisenden Sprechstelle von der Vermittlungsstelle aus

Publications (3)

Publication Number Publication Date
EP0216096A2 true EP0216096A2 (fr) 1987-04-01
EP0216096A3 EP0216096A3 (en) 1989-03-22
EP0216096B1 EP0216096B1 (fr) 1992-03-04

Family

ID=6281065

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86110895A Expired - Lifetime EP0216096B1 (fr) 1985-09-16 1986-08-06 Dispositif pour la coupure par le central d'un poste branché involontairement sur la ligne dans une connexion à deux postes pouvant être branchés alternativement sur la ligne de façon automatique

Country Status (3)

Country Link
EP (1) EP0216096B1 (fr)
AT (1) ATE73283T1 (fr)
DE (2) DE3532960C1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5706277A (en) * 1993-05-28 1998-01-06 Siemens Aktiengesellschaft Method for changing-over to standby for a transmission device for the bidirectional transmission of digital signals and arrangement for carrying out the method

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1054123B (de) * 1957-08-01 1959-04-02 Erhard Kuehnl Schaltungsanordnung fuer Fernsprechanschluesse, insbesondere Zweieranschluesse
DE1933717A1 (de) * 1969-07-03 1971-01-21 Standard Elek K Lorenz Ag Schaltungsanordnung fuer einen Zweieranschluss in Fernmelde-,insbesondere Fernsprechvermittlungsanlagen
US3843848A (en) * 1973-01-12 1974-10-22 Magnetic Controls Co Telephone looptest system
IT1149225B (it) * 1980-10-09 1986-12-03 Italtel Spa Disposizione circuitale per utenti duplex in centrali di commutazione telefonica di tipo elettronico
DE3513598A1 (de) * 1985-04-16 1986-10-16 Neumann Elektronik GmbH, 4330 Mülheim Einrichtung zur pruefung einer fernmeldeleitung zwischen einer vermittlungsstelle und einem teilnehmeranschluss von der vermittlungsstelle aus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5706277A (en) * 1993-05-28 1998-01-06 Siemens Aktiengesellschaft Method for changing-over to standby for a transmission device for the bidirectional transmission of digital signals and arrangement for carrying out the method

Also Published As

Publication number Publication date
DE3684069D1 (de) 1992-04-09
EP0216096A3 (en) 1989-03-22
DE3532960C1 (de) 1987-02-05
ATE73283T1 (de) 1992-03-15
EP0216096B1 (fr) 1992-03-04

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